"That bollard could have been a child"; On traffic safety and human behaviour in traffic

Transport and PlanningCivil Engineering and Geoscience

Distracted cycling: What do we know (PPT)

Transport and Plannin

"Dat paaltje had ook een kind kunnen zijn"; over verkeersveiligheid en gedrag van mensen in het verkeer

Transport and PlanningCivil Engineering and Geoscience

Improving road safety: Experiences from the Netherlands

Dr. Hagenzieker's research and education activities focus on the road safety effects of the transport system, with particular interest in road user behaviour aspects. Her PhD-research was on the effects of rewards on road user behaviour.Transport & PlanningCivil Engineering and Geoscience

Working towards a Meaningful Transition of Human Control over Automated Driving Systems

Automated vehicles with partial automation, supporting both longitudinal and lateral control of the vehicle, are currently available for the consumer. The consequences of driving with this type of advanced driver assistance systems is not well-known, and could cause the human driver to become out-of-the-loop, or cause other types of adverse behavioural adaptation, leading to dangerous circumstances. Therefore, understanding what the effects of driving with automated driving systems are from the human driver’s perspective is becoming imperative. By means of a literature-based approach, this paper presents a framework of human control over automated driving systems. This framework shows the quantified distribution of human behaviour over all the levels of automation. The implications, discrepancies and apparent mismatches this framework elicits are discussed, and recommendations are made to provide a meaningful transition of human control over automated driving systems.Transport and Plannin

Working towards a Meaningful Transition of Human Control over Automated Driving Systems

Transport and Plannin

Phoning, texting, operating a navigation system, and following route guidance

Engineering, Systems and ServicesTechnology, Policy and Managemen

What will the car driver do? A video-based questionnaire study on cyclists' anticipation during safety-critical situations

Introduction: Many bicycle–car crashes are caused by the fact that the driver fails to give right of way to the cyclist. Although the car driver is to blame, the cyclist may have been able to prevent the crash by anticipating the safety-critical event and slowing-down. This study aimed to understand how accurate cyclists are in predicting a driver's right-of-way violation, which cues contribute to cyclists' predictions, and which factors contribute to their self-reported slowing-down behavior as a function of the temporal proximity to the conflict. Method: 1030 participants were presented with video clips of nine safety-critical intersection situations, with five different video freezing moments in a between-subjects design. After each video clip, participants completed a questionnaire to indicate what the car driver will do next, which bottom-up and top-down cues they think they used, as well as their intended slowing-down behavior and perceived risk. Results and conclusions: The results showed that participants' predictions of the driver's behavior develop over time, with more accurate predictions (i.e., reporting that the driver will not let the cyclist cross first) at later freezing moments. A regression analysis showed that perceived high speed and acceleration of the car were associated with correctly predicting that the driver will not let the cyclist cross first. Incorrect predictions were associated with believing that the car has a low speed or is decelerating, and with reporting that the cyclist has right of way. Correctly predicting that the driver will not let the cyclist cross first and perceived risk were significant predictors of intending to slow down in safety-critical intersection situations. Practical applications: Our findings add to the existing knowledge on cyclists' hazard anticipation and could be used for the development of training programs as well as for cycling support systems.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomechatronics & Human-Machine ControlHuman-Robot InteractionTransport and Plannin

Do in-car devices affect experienced users' driving performance?

Distracted driving is considered to be an important factor in road safety. To investigate how experienced user's driving behaviour is affected by in-vehicle technology, a fixed-base driving simulator was used. 20 participants drove twice in a rich simulated traffic environment while performing secondary, i.e. mobile phone and navigation system tasks. The results show that mean speed was lower in all experimental conditions, compared to baseline driving, while subjective effort increased. Lateral performance deteriorated only during visual–manual tasks, i.e. texting and destination entry, in which the participants glanced off the forward road for a substantial amount of time. Being experienced in manipulating in-car devices does not solve the problem of dual tasking when the primary task is a complex task like driving a moving vehicle. The results and discussion may shed some light on the current debate regarding phone use hazards.Engineering, Systems and ServicesTechnology, Policy and Managemen

An international comparison of the self-reported causes of cyclist stress using quasi-naturalistic cycling

This study explores the influences of attitudes and setting on cyclists' stated causes of stress using survey techniques and quasi-naturalistic cycling in both Delft, The Netherlands and Atlanta, Georgia, USA. The study recruited 28 participants in Delft and 41 in Atlanta. Participants cycled approximately 30 min on specified routes in both cities on an instrumented bicycle. Prior to cycling, the participants filled in a written survey about their cycling habits, attitudes, and demographics. At specified points during and after the ride, participants were interviewed about their stress levels throughout the ride and the causes of those stress levels. Thematic analysis and statistical methods are used to understand the interactions of setting (country), attitudes, stated stress, and sensor data. The top three stressors were motor vehicles, pavement, and poor infrastructure; 83% of participants mentioned a motor vehicle causing stress, 64% mentioned road surface, and 58% mentioned infrastructure. The results confirm the importance of motor vehicle interaction to cyclist stress, but also highlight some new insights on stress such as the importance of pavement condition. Speed differentials between cyclists and vehicles were also shown to be important and suggested cyclists in Delft felt comfortable to travel their ideal speed. This speed preference was supported by GPS data that showed the cyclists in Delft were cycling at speeds about half (12 kph) that of the cyclists in Atlanta (24 kph). Review of close-pass events demonstrated that cyclists in Delft were more comfortable with closer passes which could be associated with their belief that motorists notice them and/or speed differences between the vehicle and bicycle. The results also suggest that number of vehicle travel lanes can have mixed impacts on cyclist stress. These findings can be taken into consideration when designing bicycle facilities to create low-stress cycling networks.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport and Plannin